Problema Solution
Three digits are select at random and without repetition from the set {2, 4, 5, 6, 8} and used to form a 3-digit whole number. What is the probability that the number will be:
A. Less than 600 B. An odd number C. A number greater than 800
Answer provided by our tutors
the number of the 3-digit numbers formed from the set {2, 4, 5, 6, 8} is 5*4*3 = 60
A. Less than 600
beginning on 2 there are 3*4 = 12 numbers
beginning on 4 there are 3*4 = 12 numbers
beginning on 5 there are 3*4 = 12 numbers
or total of 12 +12 + 12 = 36
P (less than 600) = 36/60 = 0.6 or 60%
B. An odd number
the odd number end in 5 and there are 3*4 = 12 such numbers
P(odd number) = 12/60 = 0.2 or 20%
C. A number greater than 800
all the numbers starting with 8 are bigger then 800 and there are 3*4 = 12 such numbers
P(number greater than 800) = 12/60 = 0.2 or 20%